JP3031058B2 - keyboard - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard, and more particularly, to a keyboard which has a slider functioning as a key switch and is integrally formed with a spring function to reduce the number of components, thereby realizing a low-profile and low-cost keyboard.

In recent years, in response to the spread of information processing in various fields, various input / output devices have been used for human-machine interfaces. Among them, a keyboard is most popular and widely used as an information input device.

[0003] A keyboard is generally rarely used alone, and is generally used as an input slave unit attached to a parent device. Therefore, depending on the function of the parent device, a large number of keys called a full keyboard having more than a hundred keys is used. There are various forms, from small ones such as a numeric keypad. However, in any form of keyboard, it is an important issue from the viewpoint of manufacturing technology how to respond to a demand for a small, low-profile and low-cost parent device.

[0004]

2. Description of the Related Art One of the basic components of a keyboard is a plurality of key switches arranged in parallel. There are various types of key switches, and keyboards are also classified according to the types of key switches.

[0005] In the past, the mainstream of keyboards were keyboards in which switch elements for making electrical conduction by mechanically contacting contacts were arranged on a printed circuit board. However, the method of arranging such a single key switch has become a so-called dead technology, and measures for shortening the height and reducing the price have reached the limit. Therefore, a membrane switch and a membrane keyboard using the switch have been developed as key switches aiming at lower height and lower cost.

[0006] In addition to the key switch, the keyboard is provided with a key top that is directly touched with a finger and pressed, and is provided between the key top and the switch element, and the pressing force of the key top is used to open and close the contacts of the switch element. There is a component such as an actuator that converts the data into a data.

FIG. 4 is a cross-sectional view showing an example of the configuration of a key switch of a conventional keyboard. FIG. 5 is a diagram showing the pressing characteristics of a key. FIG. 5 (A) shows the pressing characteristics of the key switch of FIG.
(B) is a pressing characteristic of the key switch excluding the spring.
In the figure, 1 is a key top, 2 is a housing, 3 is a slider, 4 is a spring, 5 is a rubber actuator, 5a is a protrusion, 6 is a membrane switch, 7 is a support panel, 8
Is an inner slider, and 10 is a key switch.

In the key switch 10 of the membrane keyboard exemplified here, first, the membrane switch 6 is supported on the support panel 7. The membrane is a thin film, and the membrane switch 6 has a structure in which dielectric sheets on which contacts are formed by screen printing or the like are stacked via a spacing sheet.

A rubber actuator 5 is used as a conversion member for opening and closing the membrane switch 6 by pressing the membrane switch 6, and is disposed on the membrane switch 6. The rubber actuator 5 has a dome shape with a bowl lying down and is constantly urged upward. Then, when the outer top is depressed, it is depressed and the projection provided on the inner top is provided.
5a presses the rubber actuator 5 to perform a closing operation.

The rubber actuator 5 is pressed by the bottom of the cylindrical inner slider 8 into which the spring 4 is inserted.
The top of the spring 4 strikes the lower top of the slider 3 to urge the slider 3 upward. This slider 3
Is fitted to the housing 2 and the key top 1
Pressing and releasing pushes up and down.

A double biasing structure is provided in which the inner slider 8 is biased upward by the rubber actuator 5 and the slider 3 is biased upward by the spring 4 fitted inside the inner slider 8. This is to improve the key pressing characteristics and to obtain a key feeling called a so-called snap action.

By the way, the pressing characteristic of a key switch using both a spring and an actuator has a hysteresis curve as shown in FIG. The horizontal axis is the pressing distance (mm), and the vertical axis is the pressing force (kgf). That is, when the keytop is pressed, the spring and the actuator descend while maintaining the load balance, and the pressing force F (repulsive force applied to the keytop) increases linearly. Then, at the point A, the vehicle rapidly drops to the point B. This steep drop of the pressing force F is due to the rubber actuator being crushed and the dome being inverted, and the key feeling of the click felt by the finger is a so-called snap action.

Then, the projection of the rubber actuator comes into contact with the membrane switch at the point B, and when further depressed, the pressing force F increases toward the point C and the membrane switch is pressed to perform the closing operation.

When the pressing force F of the key top is released, the pressure drops to the point D, then rises sharply at the point E, and returns to the original. That is, when the membrane switch is opened, the dome of the rubber actuator expands so as to bounce at the same time as the opening of the membrane switch can be obtained with a key sense from a finger.

[0015]

However, when the spring of the key switch is removed and the rubber actuator is directly pressed by the slider, the pressing characteristic as shown in FIG. 5B is exhibited. That is, when the keytop is pressed, the pressing force F rises to the point A, then gradually drops to the point B, and then rises to the point C. In such a pressing characteristic, FIG.
Since there is no sharp rise and fall of the pressing force F as shown in FIG. That is, if the structure of the key switch is simplified to reduce the number of constituent members and the assembling work is simplified, the characteristics required for the keyboard are impaired.

As described above, the key switch is constructed by combining various members in order to improve the key feeling, and has a large number of components. Therefore, not only the assembling work is complicated and it is difficult to reduce the price, but also the downsizing and reduction in height are troublesome.

Accordingly, an object of the present invention is to provide a keyboard which is integrally formed so that a slider constituting a key switch has a spring function.

[0018]

SUMMARY OF THE INVENTION The above-mentioned object is to provide a key top, a slider which is pushed down by the key top to move up and down inside the housing, and a rubber actuator which is pushed down by the slider via a spring. And a keyboard provided with a plurality of membrane switches that are pressed / released by the rubber actuator to perform closing / opening operations, wherein the slider is integrally formed so that a lower portion thereof is constricted to form the spring. Solved by a keyboard that is configured to be

[0019]

A key switch using a conventional rubber actuator is configured to generate a snap action while maintaining the load balance between an individual spring and an actuator. On the other hand, according to the present invention, the shape of the slider and the plastic The slider and the spring are integrally formed by utilizing the elasticity of the slider.

With this arrangement, the slider can be made small and low-profile, and the number of components of the key switch can be reduced, so that the keyboard assembling process can be reduced.
Thus, the price of the keyboard can be reduced.

[0021]

1 is a sectional view of a first embodiment of the present invention, FIG. 1 (A) is a sectional view in an open state, FIG. 1 (B) is a sectional view of a main view in a closed state, FIG. Is a sectional view of a second embodiment of the present invention, and FIG. 3 is a sectional view of a third embodiment of the present invention. In the figure, 1 is a key top, 2 is a housing, 3
Is a slider, 4 is a spring, 5 is a rubber actuator, 6 and a membrane switch, 6a is an upper sheet, and 10 is a key switch.

Embodiment 1 In FIG. 1, a lower part of a slider 3 is constricted to form a spring 4. The spring 4 is formed by a constricted shape and the elasticity of a plastic such as PBT, which constitutes the slider 3, and is formed integrally with the slider 3.

When the key switch 10 is open, the slider 3 is constantly urged upward by the integrally formed spring 4 and the rubber actuator 5 on which the slider 3 rides, as shown in FIG. ing.

On the other hand, when the slider 3 is depressed as shown in FIG. 1B, the spring 4 and the rubber actuator 5 descend in the housing 2 while maintaining the load balance. Then, after the rubber actuator 5 is crushed to be inverted, the membrane switch 6 is pressed to be in a closed state.

In the key switch 10 having this configuration, since the spring used in the conventional key switch and members such as the inner slider into which the spring is fitted are removed, the slider 3 can be made smaller and lower. . And
This key switch 10 has a pressing characteristic having a snap action equivalent to that of a conventional switch using a spring or an inner slider as shown in FIG.

Embodiment 2 In FIG. 2, the top of the slider 3 is the key top 1 instead of the conventional switch configuration in which the key top 1 is separately mounted on the slider 3. And it is the structure integrally formed with the spring 4 together.

In the key switch 10 having such a configuration, the key top 1 can be excluded from the number of components. Therefore, not only can the assembling work be simplified and the number of man-hours can be reduced, but also the key top 1, the slider 3 and the spring 4 can be integrally formed in one step, so that the entire manufacturing process such as procurement of members and inventory management can be rationalized. .

Embodiment 3 In FIG. 3, the upper sheet 6a of the membrane switch 6 is shown.
Is made of, for example, a polyester sheet having a thickness of about 100 μm. Therefore, the upper sheet 6a is embossed into a dome shape and elastically urged upward to have the same function as the actuator. Then, the slider 4 is pressed by a spring 4 integrally formed with the slider 3.

Then, in response to the vertical movement of the slider 3, the spring 4 and the dome-shaped upper sheet 6a are pressed and pushed up while maintaining the load balance, so that the rubber actuator 5 can be eliminated.

Thus, in the present invention, first, the spring 4 is integrated with the slider 3, then the keytop 1 is integrated with the slider 3, and further, the function of the rubber actuator 5 is given to the upper sheet 6 a of the membrane switch 6. .
Thus, the number of components of the key switch 10 can be reduced to half or less.

[0031]

According to the conventional key switch using a rubber actuator, a spring is incorporated in a slider to generate a snap action while maintaining a load balance between the spring and the actuator. The slider and the spring are integrally formed using the shape of the slider and the elasticity of the plastic. Also, the slider and the key top are integrally formed. Further, the membrane switch is provided with the function of an actuator.

As a result, the number of component parts of the key switch is reduced to less than half, troublesome assembling work can be greatly reduced, and the keyboard is reduced in size, height and cost. The invention contributes greatly.

[Brief description of the drawings]

1A and 1B are cross-sectional views of a first embodiment of the present invention, in which FIG. 1A is a cross-sectional view in an open state, and FIG.

FIG. 2 is a sectional view of a second embodiment of the present invention.

FIG. 3 is a sectional view of a third embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a configuration example of a key switch of a conventional keyboard.

5A and 5B are diagrams showing the pressing characteristics of a key, wherein FIG. 5A shows the pressing characteristics of the key switch of FIG. 4 and FIG. 5B shows the pressing characteristics of the key switch excluding a spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Key top 2 Housing 3 Slider 4 Spring 5 Rubber actuator 6 Membrane switch 6a Upper sheet 10 Key switch

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Toshio Yamaguchi 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside of Fujitsu Limited (56) References Full-scale 1987-86029 (JP, U) Full-scale 1987-98113 (JP, U) JP-A 62-118324 (JP, U) JP-A 1-139326 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01H 13/70 H01H 13 / 14

Claims (3)

(57) [Claims] 1. A key top (1) and a slider which is pressed by the key top (1) to move up and down in the inside of a housing (2).
(3), a rubber actuator (5) pressed by the slider (3) via a spring (4), and a membrane switch (closed / opened by being pressed / released by the rubber actuator (5)). 6) A keyboard in which a plurality of the sliders (3) are provided, wherein the slider (3) is integrally formed so that a lower portion thereof is constricted to form the spring (4). 2. The keyboard according to claim 1, wherein the slider (3) is integrally formed so that a top portion forms the key top (1). 3. The keyboard according to claim 1, wherein said membrane switch is embossed so that an upper sheet protrudes upward in a dome shape.